Question

A relief airplane is delivering a food package to a group of people stranded on a very small island. The island is too small for the plane to land on, and the only way to deliver the package is by dropping it. The airplane flies horizontally with constant speed of 260 mph at an altitude of 700 m. The positive x and y directions are defined in the figure. For all parts, assume that the "island" refers to the point at a distance D from the point at which the package is released, as shown in the figure. Ignore the height of this point above sea level. Assume that the acceleration due to gravity i

Answer 1

After a package is ejected from the plane, how long will it take for it to reach sea level from the time it is ejected? Assume that the package, like the plane, has an initial velocity of 260 mph in the horizontal direction.

Answer 2

initial velocity of package in y direction is zero
h = ut-1/2gt^2
t =sqrt(2gh)
t =sqrt(2*10*700)
t = 118.32sec

Answer 3

how did you know that the initial velocity was zero